Thanks for the replies. You definitely have better eyes than I do. I saw both hammers in real life and couldn't decide if one was bigger. They are about 25 miles apart.
Bottom one is definitely an h7x, serial number confirmed it. The 4x hammer only needs the swivel seals for the in and out. I still need to find the serial number.
The bigger hammer is going to need a lot of modification to the side brackets to get it mounted on the pc120 that I want it to run on.